About this calculator

Convert both durations to seconds, calculate the sum and difference, then format them as hours, minutes and seconds.

Frequently asked questions

What does the Time Duration Calculator do?

Add, subtract and compare hours, minutes and seconds. Convert both durations to seconds, calculate the sum and difference, then format them as hours, minutes and seconds.

Is the Time Duration Calculator free to use?

Yes. Every calculator on Calcurly.com is free, works in your browser without sign-up, and can be embedded on your own website.

How accurate is the Time Duration Calculator?

Results are calculated in real time using industry-standard formulas. Treat the output as a well-informed estimate — always cross-check with local regulations, product datasheets, or a qualified unit converters professional before committing to a purchase or a job.

What inputs does the Time Duration Calculator need?

Enter values for: First hours, First minutes, First seconds, Second hours, Second minutes, Second seconds. Sensible defaults are pre-filled where possible so you can start with a single change.

Can I embed the Time Duration Calculator on my own website?

Yes — copy the iframe snippet at the bottom of this page, or use the Embed Generator to customise the size. The embedded version stays in sync with the live calculator on Calcurly.com.